I am not going to pretend that I speak for all Atheists, but in my particular case you couldn't be further from the truth.

As a part of the human race, I can feel empathy for other human beings because as sentient beings we know that certain experiences are universal amongst thinking life forms. For example, I know that someone who has lost a family member feels grief, and I can sympathize. Note that I can sympathize with a loss without any reference to a supreme being, just a knowledge that all living things will die, and those that were close will miss them.

I do not feel 'left out', as that implies that I would want to be included in a religion, but was not allowed to. I do know that is not how religions work, all are welcome if they accept that religion's deity as the One True God.

Like I've said before, the difference between atheists and the religious is atheists don't care if you are religious, we'll accept you as you are.